1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
2 *
3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner.
5 *
6 * The library is free for all purposes without any express
7 * guarantee it works.
8 *
9 * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
10 */
11 #include "tomcrypt.h"
12
13 /**
14 @file lrw_decrypt.c
15 LRW_MODE implementation, Decrypt blocks, Tom St Denis
16 */
17
18 #ifdef LTC_LRW_MODE
19
20 /**
21 LRW decrypt blocks
22 @param ct The ciphertext
23 @param pt [out] The plaintext
24 @param len The length in octets, must be a multiple of 16
25 @param lrw The LRW state
26 */
lrw_decrypt(const unsigned char * ct,unsigned char * pt,unsigned long len,symmetric_LRW * lrw)27 int lrw_decrypt(const unsigned char *ct, unsigned char *pt, unsigned long len, symmetric_LRW *lrw)
28 {
29 int err;
30
31 LTC_ARGCHK(pt != NULL);
32 LTC_ARGCHK(ct != NULL);
33 LTC_ARGCHK(lrw != NULL);
34
35 if ((err = cipher_is_valid(lrw->cipher)) != CRYPT_OK) {
36 return err;
37 }
38
39 if (cipher_descriptor[lrw->cipher].accel_lrw_decrypt != NULL) {
40 return cipher_descriptor[lrw->cipher].accel_lrw_decrypt(ct, pt, len, lrw->IV, lrw->tweak, &lrw->key);
41 }
42
43 return lrw_process(ct, pt, len, LRW_DECRYPT, lrw);
44 }
45
46
47 #endif
48
49 /* $Source: /cvs/libtom/libtomcrypt/src/modes/lrw/lrw_decrypt.c,v $ */
50 /* $Revision: 1.8 $ */
51 /* $Date: 2006/06/29 01:53:13 $ */
52